Ventilation '85.

Provides the text of the 68 papers presented at the symposium, arranged under the following headings - Plenary session, Advanced developments in ventilation, Control of toxic and explosive contaminants, Advances in tracer gas use, Ventilation for residential and modern office buildings, Advances in local exhaust technology, Ventilation for control of carcin- ogens and biohazards, Ventilation measurement and control, Sources emission rates, Filters, Air recirculation and energy conservation.

Controlling indoor air pollution from tobacco smoke - models and measurements

Examines the effects of smoking rate, ventilation, surface deposition, and air cleaning on the indoor concentrations of respirable particulate matter and carbon monoxide generated by cigarette smoke. A general mass balance model is presented which has been extended to include the concept of ventilation efficiency. Following a review of the source and removal terms associated with respirable particulates and carbon monoxide, we compare model predictions to various health guidelines.

Contaminant control in the built environment: state of the art summary.

The reduction of ventilation in buildings as an energy saving measure may result in a deterioration in indoor air quality. Suggests use of contaminant control devices and summarises devices available. These are filters, electrostatic precipitators, mechanical dust collectors, scrubbers, and contaminant combustors Suggests five areas where further research is necessary.

The effect of domestic air treatment equipment on the concentration of radon daughters in a sealed room.

Reports tests of the effect of various air treatment devices on the radon daughter concentrations within a room. Test were carried out using an electrostatic precipitator, a humidifier and a dehumidifier. The ventilation rate of the room was measured using Krypton 85 as a tracer gas.< Finds that the use of a humidifier, dehumidifier or carbon filter gave no significant alteration to the radon concentrations in the room, but that the electrostatic precipitator reduced the concentration considerably and was equally effective when operated with or without the carbon filter.

Indoor radon concentrations and building materials. Control of airborne radioactivity

The daughter products of radon are chemically active materials which, when inhaled are very likely to deposit in the respiratory tract. Defines a special unit, the working level, to indicate the radiation burden from radon daughters. Reports study of exhalation rates from various building materials made by enclosing samples in containers and analysing air samples from the containers. Gives table of results. Discusses control of airborne radiation by increasing the ventilation rate, sealing room surfaces, mechanical circulation and filtration of the air.